Test-stand for testing generators



L. C, SCHAF, Lm AND W. J. HOLUDAY.

TEST STAND FOR TESTING GENERATORS.- APPLICATION FILED NOV. 20, 1920.

139mm, Patented Nov. 15, 19211..

2 SHEETS-SHEET 1.

IN V EN TORS JOSEPH 6. Sch 44 W/LL MM J #044/057.

'- "ATTORNEYQS J. C. SCHAF, 1a., AND W. J. HOLLIDAY. TEST STAND FORTESTING GENERATORS. APPLICATION FILED NOV. 20. I920.

Patented Nov. 15, 1921..

2 SHEETS-SHEET Z.

Joanne c. sonar, an, ienn wrtrrarr a. moraine-r, or mnreln'erotrs,momma.

TEST' STAND FOR, TESTING- GENERATORS.

Specification of Letters Patent.

Patented Nov. 15, 1321.

Application filed. November 20, 1920. Serial No. 425,533.

full, clear, and exact description thereof,

reference being had to the accompanying drawings, in which like numeralsrefer to like parts. p

This inven ion relates to a test stand for electric generators, andparticularly generators of the type used for generatmg cur- The teststand is used for the purpose of testing the volts and I amperegenerated at a certain R. P.

7 ing a constant R.

whereby the generator justed.

One feature of the invention consists in the, construction of the teststand whereby the generator may be driven at variable:

may be properly ad- .speeds and be driven at a constant speed regardlessof the load applied to the generator within certain limits, thusovercoming "the defects experienced in adjusting the driven, s eed ofthe'generator to a certain R. P. for testing purposes, and upon changingthe load to the generator causin the R. P. M. to vary from the speeddesire Anothe feature of the invention consists in the means formounting the driving motor upon the test stand so as to enable it to beadjustably and yieldingly engaged with the generator driving mechanismfor maintain- P. M. with a frictiondrive and prevent any slippage.

The full nature of this invention will be understood from theaccompanying drawings and the following description and claims.

Figure 1 is a side elevation of'the driving mechanism of the test standshowing an electric generator in position to be driven. lFig. 2 is aplanview looking down on Fig. 1. Fig. 3 is an end elevation. Fig. l is anenlarged side elevation of the motor base and standards 11 provided withbearings 12 in which is mounted a driving shaft 13. Upon means the shaftthere is mounted a friction wheel Y lt'adapted to be driven by thefrictional en- "gagement with the friction disk 15 driven from theelectric motor 16. The speed with which the shaft 13 is revolved by saidmotor is varied by turning the hand wheel 17 mounted on a screw shaft 18supported in the bearings 19 of the standard 11 adapted to screw throughthe traveling member 20 so as to cause it to move backward and forwardbetween the standards 11 upon the turning of a screw shaft 18.. Thetraveling member 20 is provided with a yoke 21 which extends down andengages a flanged wheel 22 secured to the friction wheel 14 which isslidably keyed upon the shaft13. By means of this construction, byturning the hand wheel 17 the friction wheel 14 is moved transversely ofthe friction disk 15, whereby it will be positioned in neutral and willnot be driven when at the center of said disk but it will be driven atvarying speeds between the center and periphery on one side thereof andat reverse varying speeds on the other side.

Mounted upon the tale 10 there is a mounting block 23 so designed as toposition and support the electric generator to be tested as'to cause itsshaft to be as nearly in 'alinement with the shaft 13 as possible. The

generator 24 is secured in position by means of a flexible metal band 24which is drawn about it and clamped tightly over the top thereof by theclamping member 26. The generator shaft is operatively connected withthe driving shaft 13 through the yielding universal chuck comprising aspirally wound cylindrical spring 27 secured at one end to the shaft 13and at the other end to the is provided with an inwardly extending pin29 in position to engage between the teeth 30 of the gear 31 mounted onthe end of the generator and forming a part thereof. By of thisconnection any torsional strain and adjustment in alinement iscompensated for by the spring connection.

The motor 16 is mounted on the base 32 which is slidably mounted on therods 33 which extend longitudinally of the motor on each side thereofand are fixedly supported upon the table 10 by the blocks 34:.Slidablymounted upon sliding blocks 35 through which said rods extend,so that said motor is adapted to slide longitudinally of the table 10,whereby the the rods 33 there are 95 chuck member 28. The chuck member28 wheel and cause it to be friction disk 15 may be moved in and out ofengagement with the friction wheel 14. In order to maintain a yieldingpressure between said friction disk and friction wheel there is provideda spiral compression spring 36 mounted on each of the rods 13 betweenthe forward block 35 and a collar 37. collar 37 is held in position bythe pin 38 adapted to be placed in the hole 39 extending diametricallythrough said rods, which will give the proper compression to thespring36 and the proper degree of driving friction.

The invention claimed is:

1. A test stand for testing generators and the like including anelectric motorhaving a friction disk, a driving shaft, a friction wheelslidably mounted on aid driving shaft so as to engage'said friction diskand be driven at variable speeds thereby, means for causin said frictionwheel to slide upon said s aft so as to adjust said wheel and cause itto be driven at variable speeds, means for operatively connecting saiddriving shaft and the generator to be tested for driving it a givenspeed at which it is tested, andmeans for mounting said motor so as tomaintain said friction disk in yielding frictional engagement with saidfriction wheel.

2. A test stand for testing generators and the like including anelectric motor having a friction disk, a driving shaft, a friction wheelslidably mounted on said driving shaft so as to engage said frictiondisk and be driven at variable speeds thereby, mean for causing saidfriction wheel to slide upon said shaft so as to adjust said driven atvariable speeds, means for operatively connecting said driving shaft andthe generator to be tested for driving it a given speed at which itistested, and 'compression springs adjustably positioned for yieldinglyforcing said motor upon a sliding base whereby said friction disk willbe yieldingly maintained against said friction wheel.

3. In combination with acdriving motor and a driven shaft, of means forfrictionally driving said shaft, including a friction disk mounted onsaid motor, a friction wheel in position to be en keyed to said shaftThe gaged by said disk, a slidable base upon which said motor ismounted, and a compression spring mounted in said base for yieldinglyforcing said motor and disk against said friction wheel under the desired pressure.

4. In combination with a driving motor and a driven shaft, of mean forfrictionally driving said shaft, including a friction disk mounted onsaid motor, a friction wheel keyed to said shaft in position to beengaged by said disk, a slidable base, upon which said motor i mounted,and a compression spring mounted in said base for yieldingly forcingsaid motor and disk against said friction wheel, andmeans for adjustinthe compression of said spring for regu ating the frictional engagementof said disk and Wheel.

5. In combination with a driving motor 'and a driven shaft, of means forfrictionally driving said shaft, including a friction disk mounted onsaid motor, a friction wheel keyed to said shaft in position to be engaged by said disk, means for yieldinglymaintaining said friction diskin engagement with said friction wheel, and a spring mounted in the baseof said motor adapted to be adjusted therein for forcing said motorforward and causing said disk to frictionally engage said wheel underthe desired yielding sp ing pressure.

6. In com ination with a generator and a driving shaft therefor, .ofmeans for con-- necting the shaft of said generator with said drivingshaft for causing said generator to be driven, including a spirallywound spring having one end secured to said shaft, a chuck membersecured to the other end of said spring, and an inwardly and radiallyextending pin in said chuck member adapted to be inserted between thegear teeth 1 on said shaft for removably connecting said chuck memberand shaft, whereby said driving shaft will drive said generator shaftthrough said spring and chick member without strain when not inalinement, V In witness whereof, we have' hereunto afiixed oursignatures. I

JOSEPH C. SCHAF, JR. WILLIAM HOLLIDAY.

